Low tin jewel metal alloy

Abstract

A bismuth-lead alloy containing lesser amounts of tin, antimony and zinc has been developed for use as a fusible metal, and particularly as a jewel metal alloy. The alloy meets the standards set by presently available jewel metals, has a lower melting temperature, better casting properties, and is less expensive than currently used alloys.

We claim: 
     
       1. A jewel metal alloy having excellent casting characteristics, low liquidus and solidus temperatures and minimal gas porosity comprising: a bismuth-lead based alloy with a bismuth-lead ratio of about 1.3 to 1.0 having about 45.0-55.0 wt. % bismuth and about 34.5-42.5 wt. % lead;   about 1.0 to 15.0 wt. % tin;   about 1.5 to 5.0 wt. % antimony;   about 0.05 to 1.00 wt. % zinc.   
     
     
       2. An alloy as claimed in claim 1 wherein the bismuth-lead compositions are about 51.3 wt. % bismuth and about 41.2 wt. % lead. 
     
     
       3. An alloy as claimed in claim 1 wherein the amount of tin is about 4.7 to 5.2 wt. %. 
     
     
       4. An alloy as claimed in claim 1 wherein the amount of antimony is about 1.8 to 3.0 wt. %. 
     
     
       5. An alloy as claimed in claim 1 wherein the amount of zinc is about 0.50 to 0.65 wt. %. 
     
     
       6. A jewel metal alloy having excellent casting characteristics, low liquidus and solidus temperatures and minimal gas porosity comprising: a bismuth-lead composition with a bismuth-lead ratio of about 1.3 to 1.0 having about 45.0-55.0 wt. % bismuth and about 34.5-42.5 wt. % lead;   about 4.7 to 5.2 wt. % tin;   about 1.8 to 3.0 wt. % antimony;   about 0.50 to 0.65 wt. % zinc.   
     
     
       7. An alloy claimed in claim 6 wherein the bismuth-lead composition has about 51.3 wt. % bismuth and about 41.2 wt. % lead. 
     
     
       8. An alloy as claimed in claim 6 wherein the amount of tin is about 5.0 wt. %. 
     
     
       9. An alloy as claimed in claim 6 wherein the amount of antimony is about 2.0 wt. %. 
     
     
       10. An alloy as claimed in claim 6 wherein the amount of zinc is about 0.50 wt. %.